黄芪提取物对结肠腺癌Caco-2细胞葡萄糖吸收的影响

目的:探讨黄芪提取物对Caco-2细胞葡萄糖吸收的影响,并探讨其作用机制。方法:采用系统溶剂法提取黄芪各部位,以Caco-2细胞为研究对象,设立空白组和黄芪各提取部位组(乙醇、石油醚、乙酸乙酯、正丁醇4个部位组)。以荧光标记2-脱氧葡萄糖(2-NBDG)做为光学探针检测黄芪各提取部位对Caco-2细胞葡萄糖吸收能力的影响。筛选出黄芪中促进Caco-2细胞葡萄糖吸收的药效部位后,对这一药效部位有效作用浓度进行考察。采用蛋白免疫印迹法(Western blot)法测定Caco-2细胞钠依赖葡萄糖转运蛋白(SGLT1)和2型葡萄糖转运蛋白(GLUT2)蛋白表达。结果:黄芪正丁醇提取部位可以促进Caco-2细胞葡萄糖的吸收,与空白组比较,黄芪正丁醇提取部位100,150 mg·L-1组Caco-2细胞葡萄糖含量升高(P0.05,P0.01);且黄芪正丁醇部位可以上调Caco-2细胞GLUT2和SGLT1蛋白的表达(P0.05,P0.01)。结论:黄芪正丁醇萃取部位可以促进Caco-2细胞葡萄糖的吸收,这一作用机制可能与SGLT1和GLUT2蛋白的调节有关。

Effect of Astragali Radix Extracts on Glucose Absorption in Colon Adenocarcinoma Caco-2 Cell

Objective: To investigate effects of Astragali Radix extracts on glucose absorption in Caco-2 cell and its relevant regulation mechanism. Method: All extracts of Astragali Radix were extracted by using systematical solvent separation method. Except for the blank group, Caco-2 cells were treated with Astragali Radix extracts, and then divided into four extraction groups (ethanol, petroleum ether, ethyl acetate, and n-butanol). The glucose absorption was detected by using the fluorescent D-glucose analog, with 2-deoxyglucose (2-NBDG) as the probe indicator. After the efficient extracts for promoting glucose absorption in Caco-2 cell was extracted from Astragali Radix, its effective concentration was studied. The expression of sodium-dependent glucose transporter 1 (SGLT1) and glucose transporter 2 (GLUT2) were detected by Western blot. Result: Astragali Radix n-butanol extract could improve glucose absorption in Caco-2 cell. Compared with control group, Astragali Radix n-butanol extract 100, 150 mg·L^-1 group showed significant increase in glucose content in Caco-2 cells (P<0.05, P<0.01). N-butyl alcohol extracts of Astragali Radix could up-regulate GLUT2 and SGLT1 of Caco-2 cells (P<0.05, P<0.01). Conclusion: Astragali Radix n-butanol extract can promote the glucose absorption in Caco-2 cells. Its mechanism of improving glucose absorption may be correlated with regulation of SGLT1 and GLUT2.